Best time to visit Kauai

The best time to visit Kauai is during summer, from June through September, when the temperature is high but still comfortable due to the cooling effects of the trade winds.

The hottest months are August and September, when temperatures may reach 33°C (91°F).

Kauai is a year-round destination, with comfortable temperatures even in winter, although you can expect more rainfall.

For outdoor activities, summer is best for both kayaking, when the sea is calmer, and hiking – the Kalalau Trail is quite slippery during the winter rains.

Kauai weather

Kauai experiences a tropical climate, with a hot season from June to September and a relatively cool, rainy season from December to March, when you can expect slightly cooler temperatures and heavy rain in the mountains and short showers elsewhere. Most of Kauai's rainfall occurs at night.

Surf conditions are seasonal: the North Shore and Westside waters are typically calm from May to September, with high surf from October to April, but the South Shore and Eastside conditions are just the opposite.

The trade winds, which blow from the north-east year-round, create microclimates, wet or dry, depending on exposure.

The leeward side – west and south coasts – of Kauai are usually hot and dry, while the windward side – east and north coasts – are generally cooler and wet. Higher elevations are cooler with occasional misty conditions.

Here are the average temperatures for Lihue, which is located on the southeast coast of Kauai.

What is the best month to visit Kauai?
The months of July, August and September are best for a beach holiday, since these months are the sunniest and hottest.

However, anytime between May and November is good, when the temperature is high but still comfortable due to the cooling effects of the trade winds.

Kauai is a year-round destination, and even in winter, from December to March, when the temperatures are a bit cooler and rainfall is more frequent the weather is generally fine and sunny.

Which is the hottest month in Kauai?
The hottest month of year in Kauai is usually August. You can expect an average high daytime temperature of 30°C (86°F), with moderate heat and humidity, and a low of 24°C (75°F).

The hot season in Kauai lasts from early-June to mid-October, with an average daily high temperature above 28°C (82°F).

July through September are the hottest months of the year in Kauai. On the warmest days, the temperature may reach a high of 33°C (91°F).

What is the humidity in Kauai?
Kauai experiences little seasonal variation in perceived humidity, with approximate average relative humidity calculated at between 72% – 77% over the course of the year.

What do the humidity conditions feel like in Kauai?
We derive the humidity comfort level – what conditions feel like – from the dew point temperature, which measures moisture content in the atmosphere: a higher dew point feels more humid, while a lower dew point feels drier.

Meteorologists agree that dew point temperature is a more consistant indication of 'absolute humidity' than relative humidity, which fluctuates with temperature. 

The average annual dew point in Kauai is 19°C (66°F), and varies over the course of the year from starting to feel humid at 17°C (62°F) to humid at 21°C (70°F). 

The more humid time of year in Kauai lasts from April through December, when you can expect the comfort level to be muggy at least 50% of the time.

The months with the most muggy days in Kauai are July, August and September, when every day in each month is muggy.

February is more comfortable, with around 11 days that feel muggy.

Which is the coolest month in Kauai?
The coolest month in Kauai is February, with an average high of 25°C (77°F) and a low of 19°C (66°F).

The cooler season lasts from mid-December to mid-April, with an average daily high temperature below 27°C (80°F).

When is it sunniest in Kauai?
The sunniest time of year in Kauai is September with eight hours of sunshine on average per day – that's around 66% of daylight hours.

The months of May through September receive the most sunshine.

For year-round sun, head to Poipu Beach and the southwest coast of Kauai.

When is the sea warmest in Kauai?
The sea is usually at its warmest in Kauai in September when the water temperature reaches 27°C (80°F), which is pleasantly warm for swimming.

The sea around Kauai is warm enough to swim year-round.

Which month has the most rain in Kauai?
March is usually the wettest month in Kauai, with an average 145mm (5.7in) of rainfall distributed across eight days. 

Rain falls throughout the year in Kauai Island. The wet season in Kauai lasts from early-October to early-May, with a greater than 20% chance of a given day being a wet day.

The drier season lasts from early-May to early-October. The month with the least rainfall in Kauai is June, with an average rainfall of 43mm (2in).

What are the windiest months in Kauai?
The windiest month of the year in Kauai is July, with an average hourly wind speed of 26 kilometres per hour (14 knots; 16 mph).

June through to late-August are the windiest months of the year in Kauai, with average wind speeds of more than 23 kilometres per hour (12 knots; 14 mph).

It's less windy from late-August through to early-June. The calmest month of the year in Kauai is January, with an average hourly wind speed of 20 kilometres per hour (10 knots; 12 mph).

The predominant wind direction in Kauai is from the east throughout the year.

Kauai Weather Averages

Jan Feb Mar Apr May Jun Jul Aug Sep Oct Nov Dec
Average high temperature (°C)
26 25 26 26 28 28 29 30 30 29 27 26
Average low temperature (°C)
19 19 20 21 22 23 24 24 24 23 22 20
Average daily sunshine (hrs)
6 7 7 8 8 8 8 9 8 7 6 5
Average daily daylight (hrs)
11 11 12 13 13 13 13 13 12 11 11 11
Comfort level – heat
Low warm icon Low warm icon Low warm icon Low warm icon Moderately warm icon Moderately warm icon Moderately warm icon Moderately warm icon Moderately warm icon Moderately warm icon Moderately warm icon Low warm icon
Comfort level – humidity (#muggy days)
13 11 14 17 22 28 30 30 29 29 23 17
Average dew point temperature (°C)
17 17 18 19 19 20 21 21 21 21 20 19
Average relative humidity (%)
75 74 74 74 74 73 73 73 72 74 76 77
UV Index (max)
7 9 10 11 11 11 11+ 11+ 11 9 7 6
Average days of rainfall (≥1mm)
8 8 7 5 4 3 5 5 5 7 7 8
Average monthly rainfall (mm)
69 97 145 51 56 43 46 59 58 85 101 119
Average wind speed (km/h)
20 21 23 24 22 25 26 24 22 21 23 22
Average sea temperature (°C)
24 24 24 24 25 25 26 26 27 27 26 25
Lihue, Kauai, Hawaii

Holiday seasons

High season: From mid-December through April, and from June through August – expect to pay top dollar for accommodations, car rentals, and airfare.

Low season: For the best hotel rates and airfares, visit in spring from mid-April to mid-June and during autumn from September to mid-December.

Note: The last week in April and early May coincide with three major Japanese holidays.

Source: Meteorological data for Kauai is based on weather statistics gathered for the 30-year period 1992 to 2021 by the National Weather Service, United States National Oceanic and Atmospheric Administration (NOAA) from the closest weather station: Lihue Airport (LIH), located on the southeast coast of Kauai, less than 3km (2mi) east of Lihue.

Advice on the best time to visit a particular destination is based on average local weather statistics, when the weather conditions are generally better than at other times of the year. We consider high and low temperatures, risk of rain (and thunderstorms, etc.), amount of sunshine and sea temperature. For general outdoor activities we favour clear, rainless days with a temperature range between 18°C (64°F) and 27°C (80°F); and for hot-weather activities we favour clear, rainless days with a temperature range between 24°C (75°F) and 32°C (89°F). Often, the best times to visit correspond to high season and therefore involve higher prices.

Latest update: Best time to visit Kauai: 10 May, 2024

Disclaimer: The information on this site is provided as is, without any assurances as to its accuracy or suitability for any purpose. Weather data and conditions at any given location and time are unpredictable and variable. We assume no responsibility and can not be held legally responsible for any decisions made on the basis of the information presented on this site.